Load-aware virtual network service over a software defined data center network

Using virtual networks is a good solution to provide customized networking services in the cloud and to isolate the performance of applications running in the cloud. Cloud providers usually oversubscribe their data centers to reduce the costs imposed to customers and naturally, oversubscription can lead to network overload. If the situation is not managed carefully, it can hurt the customers´ experience with the cloud and can also violate the service level agreement between the provider and the customers. This work presents the prototype of a centralized system which is implemented over a software defined data center network and provides a virtual network service that is sensitive to the load in the data center and tries to balance the load by reconfiguring the mapping of the virtual links. So, in an oversubscribed data center, the effects of any virtual network´s traffic on other virtual networks´ traffic would be reduced. The results of the experiments show that the system can reduce the packet loss in the data center and can increase the aggregate bandwidth that each virtual network receives over its whole life in the data center.